Apparatus and method for ionizing radiation contaminated wastewater treatment

Abstract

The present application relates to the field of sewage treatment, and particularly relates to a device and method for ionizing radiation sewage treatment. A sewage treatment device comprises: a container for carrying sewage; a plurality of spraying components arranged on the side wall of the container, the number of the spraying components is greater than or equal to 2, and the spraying components are arranged in an up-down manner, for spraying the sewage to be treated into the container in a parabolic shape; and an irradiation component for emitting an electron beam or gamma rays, and the electron beam or gamma rays is projected on the parabolic surface of the sewage to be treated. The device and method can effectively relieve the pressure of sewage treatment, and the electron beam can be fully absorbed in the sewage by designing different flow rates for different nozzles.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment, and more specifically to an apparatus and method for treating wastewater by ionizing radiation. Background Technology

[0002] Compared with traditional processes, ionizing radiation technology is particularly effective in treating heavy industrial wastewater with high COD. It not only breaks through the bottleneck of poor performance of traditional processes in wastewater treatment, but also has the characteristics of being economical, green, and simple in process for large-scale wastewater treatment.

[0003] Currently, ionizing radiation technology has not been widely adopted for the treatment of large-scale industrial wastewater. Innovative processes to improve the treatment efficiency of ionizing radiation technology mainly focus on its combination with traditional processes and the innovation of consumable reagent processes used in the process. There is relatively little research on the design of wastewater treatment equipment processes.

[0004] Therefore, the discovery of an apparatus and method for treating ionizing radiation wastewater is of great significance to improving the efficiency of ionizing radiation wastewater treatment technology. Summary of the Invention

[0005] The purpose of this invention is to overcome the aforementioned problems in the prior art and provide an apparatus and method for treating ionizing radiation wastewater. The apparatus and method of this invention can effectively alleviate the pressure on wastewater treatment by designing different flow rates for different nozzles, ensuring that ionizing radiation is fully absorbed in the wastewater.

[0006] A first aspect of the present invention provides a wastewater treatment apparatus, comprising: a container for holding wastewater; a jetting component located on the side wall of the container, the number of the jetting components being greater than or equal to 2 and arranged vertically for jetting the wastewater to be treated into the container in a parabolic manner; and an irradiation component for emitting an electron beam or gamma rays, wherein the electron beam or gamma rays are projected onto the parabolic surface of the wastewater to be treated.

[0007] A second aspect of the present invention provides a method for wastewater treatment, performed in the apparatus described in the first aspect of the present invention, the method comprising: the wastewater to be treated being ejected in a parabolic shape through the jetting component, and falling into a container after being irradiated by an electron beam or gamma rays emitted by the electron beam irradiation component.

[0008] By employing the above technical solution, the present invention has at least the following advantages compared with the prior art:

[0009] (1) The device and method for treating ionizing radiation wastewater of the present invention can effectively alleviate the pressure of wastewater treatment and improve the efficiency of wastewater treatment. By designing different flow rates for different nozzles, the electron beam can be fully absorbed in the wastewater.

[0010] (2) The device and method for treating wastewater by ionizing radiation of the present invention can effectively degrade high molecular organic compounds, especially for high-concentration organic compounds that are difficult to degrade and have long chains.

[0011] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein. Attached Figure Description

[0012] Figure 1 The diagram shown is a schematic diagram of a device according to an embodiment of the present invention.

[0013] Explanation of reference numerals in the attached figures

[0014] 1. Wastewater; 2-1. First spray component; 2-2. Second spray component; 3-1. First water film; 3-2. Second water film; 4. Container; 5. Discharge port; 6. Electron beam. Detailed Implementation

[0015] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0016] The inventors of this invention discovered that current ionizing radiation technologies, such as electron beam irradiation, mostly use a single nozzle for wastewater treatment. A major problem is that the absorbed dose of the electron beam in wastewater decreases with increasing incident depth, and the degradation rate of organic pollutants in wastewater is positively correlated with the absorbed dose. Therefore, in actual wastewater treatment, to avoid reducing treatment efficiency, the absorbed dose needs to exceed a certain threshold, which increases energy consumption. Simultaneously, the radiation of residual electron beam energy causes material heating and damage, increasing material loss. Furthermore, additional shielding measures are required to protect against the radiation of residual electron beam energy. To balance the relationship between wastewater treatment quality and treatment time, the inventors of this invention improved the device and method, achieving the goal of increasing wastewater treatment efficiency.

[0017] One specific implementation of a wastewater treatment device is as follows: Figure 1 As shown, it includes: a container 4 for holding sewage; and spraying components located on the side wall of the container, wherein the number of spraying components is greater than or equal to 2 and arranged vertically (e.g., Figure 1The diagram shows two spraying components 2-1 and 2-2 for spraying the wastewater to be treated into the container 4 in a parabolic manner 3-1 and 3-2; and an irradiation component for emitting an electron beam or gamma ray 6, which is projected onto the parabolic surface of the wastewater to be treated.

[0018] The container is also provided with a discharge port 5 at the bottom.

[0019] In one example, the apparatus further includes a catalyst support component for supporting the catalyst; the catalyst support component is located in the middle and / or bottom of the container such that the catalyst is in contact with the parabolic surface and / or with the wastewater at the bottom of the container.

[0020] The steps of irradiating the wastewater with an electron beam and contacting the wastewater with the catalyst can be performed simultaneously or sequentially at intervals. When performed sequentially at intervals, the interval is ≤1 min, preferably ≤30 s, and more preferably ≤10 s.

[0021] The contact method between the catalyst support component and the wastewater is not limited. The catalyst support component may already exist in the wastewater; alternatively, the wastewater may first be irradiated by an electron beam irradiation device and then flow through a flow path containing the catalyst support component.

[0022] In one example, the wastewater flows through a flow path containing a catalyst support component, and the residence time of the water in the ionization catalyst unit is 1s-20min, preferably 0.5min-5min.

[0023] In one instance, the catalyst support component may already be present in the wastewater.

[0024] The spraying component is provided with a nozzle, the length of which matches the scanning width of the electron beam. The width of the nozzle depends on the energy of the electron beam, that is, the length of the nozzle is the same as the scanning width of the electron beam.

[0025] In general, to improve the utilization rate of the electron beam energy, the water film is relatively thin, so the nozzle has a large aspect ratio.

[0026] In one example, the nozzle has an outlet with a length of 20cm-200cm and a width of 0.5cm-5cm.

[0027] Preferably, the nozzle has a length of 100cm-150cm and a width of 1cm-3cm.

[0028] In one example, the distance between two adjacent spray components arranged vertically is 1cm-100cm (e.g., 1cm, 5cm, 10cm, 20cm, 30cm, 40cm, 50cm, 60cm, 70cm, 80cm, 90cm), preferably 10cm-40cm. By controlling the distance between two adjacent spray components, the wastewater sprayed by the lower spray component can effectively utilize the attenuated electron beam, maximizing efficiency and enabling the treatment of more wastewater in a shorter time with the same energy consumption.

[0029] The topmost spray component is n, called the first spray component. The lower spray component adjacent to the first spray component is n-1, called the second spray component. The lower spray component adjacent to the second spray component is n-2, called the third spray component. The naming of other spray components follows the same pattern.

[0030] In one instance, such as Figure 1 As shown, the spraying component includes a first spraying component 2-1 and a second spraying component 2-2.

[0031] In one example, the spraying component includes a first spraying component, a second spraying component, and a third spraying component.

[0032] In this invention, the number of the spraying components can be greater than or equal to 2.

[0033] A second aspect of the present invention provides a method for wastewater treatment, performed in the apparatus described in the first aspect of the present invention, the method comprising: the wastewater to be treated being ejected in a parabolic shape through the jetting component, and falling into a container after being irradiated by an electron beam or gamma rays emitted by the electron beam irradiation component.

[0034] In one example, the wastewater to be treated is in contact with the catalyst on the catalyst support while being irradiated by the electron beam or gamma rays, and / or, the wastewater to be treated is in contact with the catalyst on the catalyst support at the bottom of the container.

[0035] In one example, the water flow velocity of the jet component is 0.01-6 m / s (e.g., 0.01 m / s, 0.05 m / s, 0.1 m / s, 0.2 m / s, 0.4 m / s, 0.5 m / s, 1 m / s, 2 m / s, 3 m / s, 4 m / s, 5 m / s, 6 m / s).

[0036] In one example, the water flow velocity of the uppermost jet component is 0.2-6 m / s.

[0037] In one example, along the range direction of the electron beam or gamma ray irradiation, the water flow velocity of the vertically adjacent jet components decreases from top to bottom by 10%-90%, preferably 60%-80%.

[0038] It is generally believed that water flow velocity is related to treatment efficiency; slower flow results in better treatment efficiency but lower treatment volume and higher cost, while faster flow results in poorer treatment efficiency but higher treatment volume and lower cost. The inventors of this invention have discovered that by controlling a suitable water flow velocity and setting the water flow velocity of the jetting component to decrease at an appropriate rate, the absorbed dose of the electron beam can decrease with the incident depth, thereby increasing the contact time between the wastewater and the electron beam or gamma rays. This allows for better treatment of the wastewater in a direction farther from the electron beam or gamma rays, thus achieving a larger treatment volume and lower cost while ensuring treatment efficiency.

[0039] In one instance, the absorbed dose of the electron beam or gamma rays is 0.5 kGy-50 kGy, which can be adjusted according to the thickness of the water film in the wastewater to be treated.

[0040] In one example, the energy of the electron beam irradiation is 1.5MeV-3.0MeV, and the beam current intensity is 20mA-150mA, which can be adjusted according to the thickness of the water film in the wastewater to be treated.

[0041] The treatment process of this invention utilizes the combined action of ionizing radiation and a catalyst to treat industrial organic wastewater and improve the degradation effect of organic pollutants.

[0042] This invention can use various catalysts that can be combined with ionizing radiation.

[0043] In one instance, the wastewater is wastewater containing high molecular weight organic compounds.

[0044] The scope of application of this invention is not particularly limited to the range of "high molecular weight organic compounds." It has a catalytic degradation effect on various high molecular weight organic compounds, such as some organic compounds commonly found in wastewater with high COD. The molecular weight of the term "high molecular weight" is not particularly limited, but from the perspective of the catalytic function of this invention, any organic compound that can be degraded or needs to be degraded can be understood as "high molecular weight," for example, a molecular weight of 5 kDa or higher.

[0045] The ionization irradiation catalytic unit of this invention can be used in conjunction with various wastewater treatment methods, such as Fenton oxidation, ozone catalytic oxidation, membrane filtration, flocculation, and reverse osmosis. However, in practice, the organic wastewater treatment process of this invention can achieve satisfactory water treatment results simply by using the ionization catalytic unit in conjunction with a conventional biochemical unit.

[0046] In this invention, the terms "first," "second," etc., are used to distinguish similar objects, not to describe a specific order or sequence.

[0047] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] The water quality indicators of the wastewater to be treated used in the examples are shown in Table 1. In addition, Table 1 also includes the classification indicators specified in GB18918-2002 "Discharge Standard of Pollutants for Municipal Wastewater Treatment Plants".

[0049] Table 1

[0050]

[0051] Preparation Example

[0052] Catalyst preparation

[0053] (1) Weigh 1 mol of manganese chloride, 1 mol of cobalt chloride, 1 mol of hydrated nickel chloride and 1 mol of cerium chloride and dissolve them in 1 L of deionized water to obtain a mixed metal salt solution; use KOH solution as a precipitant and slowly add it to the mixed metal salt solution, and continue stirring at room temperature for 12 h; wash the obtained solid precipitate three times with deionized water and dry it at 80 °C for 2 h;

[0054] (2) The catalyst material obtained in step (1) is placed in a muffle furnace and heated to 450°C at a rate of 2°C / min, and then calcined for 2 hours to obtain a catalyst material containing Mn, Co, Ni and Ce multi-metals.

[0055] (3) Dissolve 100g of sodium alginate powder uniformly in deionized water at 80℃; then mix it uniformly with the multi-metal catalyst material prepared in (2). Slowly add 8% calcium chloride solution dropwise. After 15 min, soak the catalyst in deionized water for 6-24 h to obtain the sodium alginate-supported multi-metal composite catalyst.

[0056] Example 1

[0057] The wastewater from dyeing and printing to be treated will pass through the following units in sequence:

[0058] (1) Coarse filtration unit: Add polymer to the sewage, aerate it, and then enter the sludge-water separation device to remove solids;

[0059] (2) Biochemical unit: anaerobic bioreactor, residence time is 2 hours;

[0060] (3) Ionization irradiation catalytic unit: Wastewater enters the flow channel and is irradiated above the flow channel with an energy of 10 MeV and a beam current of 2 mA; two nozzles are set up and named first nozzle and second nozzle in sequence from the direction of electron beam irradiation. The first nozzle is 1 m long and 3 cm wide with a water flow velocity of 0.3 m / s; the second nozzle is 1 m long and 1.5 cm wide with a water flow velocity of 0.12 m / s. The distance between the first nozzle and the second nozzle is 20 cm; the gel loaded with multi-metal catalyst is dispersed in the wastewater and then the solid gel component is filtered.

[0061] (4) Biochemical unit: facultative / aerobic biochemical reactor, which is equipped with enzyme floating packing material and has a residence time of 10 hours;

[0062] (5) Fine filtration unit: Residual pollutants are removed by activated sand filtration. The water from the outlet of the fine filtration unit is collected for testing.

[0063] Example 2 is used to illustrate the effect of nozzle distance on the treatment effect.

[0064] Example 2a

[0065] It is basically the same as Example 1, except that the distance between the first nozzle and the second nozzle in step (3) is 40cm.

[0066] Example 2b

[0067] It is basically the same as Example 1, except that the distance between the first nozzle and the second nozzle in step (3) is 80cm.

[0068] Example 3 is used to illustrate the effect of water flow velocity in the nozzle on the treatment effect.

[0069] Example 3a

[0070] It is basically the same as Example 1, except that the water flow velocity of the second nozzle in step (3) is 0.2m / s.

[0071] Example 3b

[0072] It is basically the same as Example 1, except that the water flow velocity of the second nozzle in step (3) is 0.05 m / s.

[0073] Example 4

[0074] The process is basically the same as in Example 1, except that in step (3), a third nozzle is set below the second nozzle, with a distance of 50cm from the second nozzle. The third nozzle is 1m long, 1cm wide, and has a water flow velocity of 0.02m.

[0075] Comparative Example 1

[0076] It is basically the same as Example 1, except that only the first nozzle is retained in step (3).

[0077] The treated water obtained in the above embodiments was subjected to water quality testing, and the results are summarized in Table 2.

[0078] Table 2

[0079]

[0080] As can be seen from Table 1, compared with Comparative Example 1 which only has one nozzle, the present invention can effectively balance treatment effect and treatment volume by setting multiple nozzles arranged vertically and controlling appropriate water flow speed and appropriate decrease amplitude.

[0081] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combining the various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A sewage treatment apparatus characterised in that, The device comprises: a container for carrying sewage; a plurality of spraying components arranged on the side wall of the container, the spraying components are arranged in an up-down manner, and the number of the spraying components is equal to or greater than 2, for spraying the sewage to be treated into the container in a parabolic manner; an irradiation component for emitting an electron beam or gamma rays, and the electron beam or gamma rays is projected on the parabolic sewage to be treated; the distance between two adjacent spraying components arranged in an up-down manner is 1 cm-50 cm; the water flow velocity of the uppermost spraying component is 0.2-6 m / s; the water flow velocity of the spraying components arranged in an up-down manner decreases from top to bottom, and the decreasing amplitude is 60%-80%; the spraying component is provided with a nozzle, and the length of the water outlet of the nozzle is 20 cm-200 cm, and the width is 0.5 cm-5 cm; the device further comprises a catalyst carrying component for carrying a catalyst; the catalyst carrying component is arranged in the middle and / or bottom of the container, so that the catalyst is in contact with the parabolic sewage and / or the sewage at the bottom of the container.

2. A method of sewage treatment, characterized in that, The method is carried out in the device of claim 1, and the method comprises: spraying the sewage to be treated through the spraying components in a parabolic manner; irradiating the parabolic sewage by the electron beam or gamma rays emitted by the irradiation component, and then making the irradiated sewage fall into the container; and decreasing the water flow velocity of the adjacent spraying components arranged in an up-down manner along the direction of the electron beam or gamma rays, and the decreasing amplitude is 10%-100%.

3. The method of claim 2, wherein, The sewage to be treated is in contact with the catalyst on the catalyst carrying component while being irradiated by the electron beam or gamma rays, and / or the sewage to be treated is in contact with the catalyst on the catalyst carrying component at the bottom of the container.

4. The method according to claim 2 or 3, characterized in that, The dose of the electron beam or gamma rays is 1 kGy-50 kGy.

5. The method according to claim 2 or 3, characterized in that, The energy of the electron beam is 1.5 MeV-3 MeV, and the beam current intensity is 20 mA-150 mA.

6. The method of claim 3, wherein, The catalyst is a catalyst comprising transition elements and / or rare earth elements.

7. The method of claim 2, wherein, The sewage is sewage containing high-molecular organic compounds.

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